add mesa +swrender variants (gallium software/off-screen rendering) (#4602)

- +swrender variant lets you compile an off-screen only version for
  software rendering on clusters.

- +swrender+llvm for using llvm for the software pipe

- added newer versions (17.1 and 13.0) and corrected the url location
  to use the canonical location.

var/spack/repos/builtin/packages/mesa/package.py

@@ -26,36 +26,87 @@
 
 
 class Mesa(AutotoolsPackage):
-    """Mesa is an open-source implementation of the OpenGL
+    """Mesa is an open-source implementation of the OpenGL specification
-    specification - a system for rendering interactive 3D graphics."""
+     - a system for rendering interactive 3D graphics."""
 
     homepage = "http://www.mesa3d.org"
-    url      = "http://ftp.iij.ad.jp/pub/X11/x.org/pub/mesa/12.0.3/mesa-12.0.3.tar.gz"
+    url      = "https://mesa.freedesktop.org/archive/13.0.6/mesa-13.0.6.tar.xz"
+    list_url = "https://mesa.freedesktop.org/archive"
+    list_depth = 2
 
-    version('12.0.3', '60c5f9897ddc38b46f8144c7366e84ad')
+    version('17.1.3', '1946a93d543bc219427e2bebe2ac4752')
+    version('13.0.6', '1e5a769bc6cfd839cf3febcb179c27cc')
+    version('12.0.6', '1a3d4fea0656c208db59289e4ed33b3f')
+    version('12.0.3', '1113699c714042d8c4df4766be8c57d8')
+
+    variant('swrender', default=False,
+        description="Build with (gallium) software rendering.")
+
+    variant('llvm', default=False,
+        description="Use llvm for rendering pipes.")
 
     # General dependencies
     depends_on('python@2.6.4:')
     depends_on('py-mako@0.3.4:', type=('build', 'run'))
     depends_on('flex@2.5.35:', type='build')
     depends_on('bison@2.4.1:', type='build')
+    depends_on('pkg-config@0.9.0:', type='build')
+
+    # Off-screen with llvmpipe
+    # Note: there must be a better way of selecting the preferred llvm
+    depends_on('llvm+link_dylib', when='+llvm')
 
     # For DRI and hardware acceleration
     depends_on('libpthread-stubs')
     depends_on('libdrm')
     depends_on('openssl')
     depends_on('libxcb@1.9.3:')
-    depends_on('libxshmfence@1.1:')
+    depends_on('libxshmfence@1.1:', when='~swrender')
-    depends_on('libx11')
+    depends_on('libx11', when='~swrender')
-    depends_on('libxext')
+    depends_on('libxext', when='~swrender')
-    depends_on('libxdamage')
+    depends_on('libxdamage', when='~swrender')
     depends_on('libxfixes')
+    # depends_on('expat', when='~swrender')
+    depends_on('libelf', when='+llvm~swrender')
 
-    depends_on('glproto@1.4.14:', type='build')
+    depends_on('glproto@1.4.14:', type='build', when='~swrender')
-    depends_on('dri2proto@2.6:', type='build')
+    depends_on('dri2proto@2.6:', type='build', when='~swrender')
-    depends_on('dri3proto@1.0:', type='build')
+    depends_on('dri3proto@1.0:', type='build', when='~swrender')
-    depends_on('presentproto@1.0:', type='build')
+    depends_on('presentproto@1.0:', type='build', when='~swrender')
-    depends_on('pkg-config@0.9.0:', type='build')
 
     # TODO: Add package for systemd, provides libudev
     # Using the system package manager to install systemd didn't work for me
+
+    def configure_args(self):
+        spec = self.spec
+        args = []
+        drivers = []
+        if '+swrender' in spec:
+            drivers = ['swrast']
+            # Needs +llvm, but also C++14? -> drivers.append('swr')
+            args.extend([
+                '--disable-dri',
+                '--disable-egl',
+                '--disable-gbm',
+                '--disable-gles1',
+                '--disable-glx',
+                '--disable-xvmc',
+                '--enable-texture-float',
+                '--enable-gallium-osmesa',
+            ])
+
+        if '+llvm' in spec:
+            if self.spec.version < Version('17'):
+                args.append('--enable-gallium-llvm')
+            else:
+                args.append('--enable-llvm')
+            if '+link_dylib' in self.spec['llvm']:
+                args.append('--enable-llvm-shared-libs')
+            else:
+                args.append('--disable-llvm-shared-libs')
+            args.append('--with-llvm-prefix=%s' % spec['llvm'].prefix)
+
+        if drivers:
+            args.append('--with-gallium-drivers=' + ','.join(drivers))
+
+        return args